Running without radiator caps???

**KBR** · December 16th, 2007 12:15 PM

Originally Posted by t2erns

theory: kung bakit kailangan pressure tight ang engine cooling system (that includes the rad cap). plain water and at atmospheric pressure will boil sa 100 deg C, raising the pressure will raise the boiling point (boyle's law ba un or charle's law he he forgot ko na). kaya kailangan pressurize ang system and adding coolant will also raise the boiling point.

^^I strongly agree..

also, man.. buti nalang na uwi pa ang kotse!! anywayz, running an engine (specially gasoline engines) w/out a radiator cap is a NO NO! since it will cause overheating.. which can lead to all sorts of preoblems, like a Blown Head Gasket and a cracked Cylinder Head.

pero pag Diesel engines... ok pa.. since I remembered driving one of our Mercedes-Benz 300D for about an hour.. then later found out it didnt have a damn radiator cap!! good thing though Diesel engines runs a little cooler than Gasoline engines (due to lower internal combustions)... making Diesel engines almost not to overheat at all! LOLz!

aite, peace.

**mbeige** · December 16th, 2007 12:43 PM

*KBR, I hope your 300D was the w123, and not the w124 300D sedan! The w123's have engines made out of iron block and head but the w124 diesels have aluminum heads so it is still prone to overheating and head gasket failure or engine head warping like newer cars are.

**KBR** · December 16th, 2007 01:26 PM

Originally Posted by mbeige

*KBR, I hope your 300D was the w123, and not the w124 300D sedan! The w123's have engines made out of iron block and head but the w124 diesels have aluminum heads so it is still prone to overheating and head gasket failure or engine head warping like newer cars are.

wasSup bro, well we had a W123 '85 300D and a W124 '87 300D. both turbocharged. and yup, the W124 300D had a aluminum head.

sorry OT:

anywayz, I got rid of our '87 300D earlier this year and sold it for $800! it was a great car and we put ALOT of miles into it (360K miles). I sold it since that we had too many cars and it had a bad turbo and transmission.

but we still have our '85 300D and its still running strong! except for that loud a$$ dieseld engine.. its annoying!

aite, peace.

**mbeige** · December 16th, 2007 01:56 PM

Bro if you were any closer I would have invited you to our Pinoy Benz meet down here in Buena Park. I have an '83 300D myself that I drive daily. Wow $800! Agree with you, the diesels idle cold. I have to drive mine in order for it to warm up these days, tamang tama when I reach the freeway entrance ramp it's just warmed up, perfect! That's around a 10 minute drive from our place.

Alright, back to regular programming... :-)

**pup2** · December 16th, 2007 02:14 PM

Since nakabili na siya, I think he's now aware of the pitfalls of running without a cap. As an additional advice, I'd suggest he buy a GOOD cap. Kasi yung generic/poor quality caps, bukod sa madali kalawangin ay madali din lumutong yung rubber seal sa neck nung cap. At medyo mahirap po mag-trace ng leak lalo kung nag uumpisa pa lang. Salamat.

**gooseflights** · December 17th, 2007 08:30 AM

Once na rin nangyari sa akin ito. Nag-flush ako ng tubig ng radiator ko pero nakalimutan ko ibalik yun cap. I drove my car for around 12km without radiator cap. When i was going to park, me naamoy akong parang nasusunog. I open up my window to check kung saan galing yun amoy. I found out na galing pala sa hood ko. I immediately check my temp gauge, mataas yun temp. Pagbukas ko ng hood, wala palang takip yun radiator at halos matuyo na rin yun laman niyang tubig. Nilagyan ko lang ng tubig yun radiator and this time sinuguro kong nakalagay yun rad cap ko.

So far okay pa rin naman yun kotse.

**Cobalt Blue** · December 20th, 2007 09:12 PM

Nangyayari rin yan pag tabingi ung lagay ng cap pero maynabibili naman ung custom ung chrome at iba pang arte

**grecoski** · March 3rd, 2008 05:04 PM

pag wlang rad cap prang my butas din radiator mo dhil karga k ng karga ng tubig, bkas ng bukas ng hood abala p imbes na nkfocus ka sa ibang gagawin....

**XTO** · March 3rd, 2008 06:00 PM

yep kung tumaas lang at hindi umabot sa redline you're fine kasi kung inantay at pinuwersang ginamit yan at redline eh tirik yan at malamang bingkong ang block at overhaul ang punta.

Pwedeng walang radiator cap provided inalis din ang thermostat para continuous ang water circulation….pero dahil sa nakalimutan or na-misplaced ang cap hindi na mag-o-open ang thermostat niyan kaya ang tendency is to boil until mag dry ang naiwang tubig sa block. Palit nalang ng radiator cap. I prefer FM (Federal Mogul brand

Kaya ako even fuel lid ako mismo nagsasara. Maraming balasubas na gas boy eh.

**nickel68** · April 17th, 2008 06:17 PM

Guys, yung mga jeep they can run the engine without radiator cap kasi yung mga tank nila ay oversize na yan compared to the cars. I worked in radiator company in Laguna (as design engineer) and at present nasa middle east ako same field pa rin. Yung sa kotse it was designed to be compact, kaya very limited lang yung volume ng coolant. Please note the normal boiling point ng plain water is 100 C at sea level. Talking about the coolant such Ethylene Glycol, yes it helps prevent corrosion, the same time lubricates the pump, and it will bring up the the boiling point of the coolant. But it will somewhat reduce the heat rejection on the radiator. Dont worry all the radiators were designed with the used of coolant (water+E.G.).